Factors predicting efficacy of oxaliplatin in combination with 5-fluorouracil (5-FU) +/- folinic acid in a compassionate-use cohort of 481 5-FU-resistant advanced colorectal cancer patients.

A statistical analysis was performed on the patient data collected from two compassionate-use programmes using oxaliplatin (Eloxatin(R)) + 5-fluorouracil (5-FU) +/- folinic acid (FA), to identify predictive factors for oxaliplatin-based salvage treatment in patients with 5-FU-resistant advanced colorectal cancer (ACRC). 481 5-FU-resistant ACRC patients, most with performance status < or = 2, > or = 3 involved sites, and > or = 2 prior lines of chemotherapy, received oxaliplatin + 5-FU +/- FA. Prognostic factors associated with overall response rate (ORR), time to progression (TTP) and overall survival (OS) were identified using univariate and multivariate logistic and/or Cox proportional hazards analyses. The ORR was 16% (95% CI: 13-20), the median TTP was 4.2 months (95% CI: 3.4-4.6), and the median OS was 9.6 months (95% CI: 8.6-10.6). The multivariate analysis indicated poor (> or = 2 WHO) performance status (PS), a large number of prior chemotherapy regimens (> or = 3), a low baseline haemoglobin level (< 10 g/dl), and a triweekly (vs biweekly) treatment administration schedule as significantly associated (P< 0.05) with a lower ORR. Sex (male), number of organs involved (> or =3) and alkaline phosphatase (AP) level (> or = 2 x the upper limit of normal) were associated (P< 0.05) with shorter TTP. Poor PS, a large number of organs involved, and elevated AP were independently and significantly correlated with shorter OS. Our analysis identified a relationship between efficacy results of oxaliplatin + 5-FU +/- FA treatment in 5-FU-resistant ACRC patients and baseline prognostic factors related to PS, extent of disease and number of prior regimens. Copyright 2001 Cancer Research Campaign.